1. Field of the Invention
The present invention relates to a driving module, and more particularly, to a driving module realized without components of the traditional high-voltage process.
2. Description of the Prior Art
A liquid crystal display (LCD) is a flat panel display which has the advantages of low radiation, light weight and low power consumption and is widely used in various information technology (IT) products, such as notebook computers, personal digital assistants (PDA), and mobile phones. An active matrix thin film transistor (TFT) LCD is the most commonly used transistor type in LCD families, and particularly in the large-size LCD family. A driving system installed in the LCD includes a timing controller, source drivers and gate drivers. The source and gate drivers respectively control data lines and scan lines, which intersect to form a cell matrix. Each intersection is a cell including crystal display molecules and a TFT. In the driving system, the gate drivers are responsible for transmitting scan signals to gates of the TFTs to turn on the TFTs on the panel. The source drivers are responsible for converting digital image data, sent by the timing controller, into analog voltage signals and outputting the voltage signals to sources of the TFTs. When a TFT receives the voltage signals, a corresponding liquid crystal molecule has a terminal whose voltage changes to equalize the drain voltage of the TFT, which thereby changes its own twist angle. The rate that light penetrates the liquid crystal molecule is changed accordingly, allowing different colors to be displayed on the panel.
In general, the gate driver needs to generate scan signals with an enormous voltage range, to turn on the transistors of the LCD. Thus, an output stage of the traditional gate driver needs to be realized by transistors of a high-voltage process, for avoiding the huge voltage difference between different nodes of the transistor damages the transistor when generating the scan signals with the enormous voltage range. However, the manufacture cost of the driving system would be significantly increased by using the transistors of the high-voltage process. How to reduce a number of the high-voltage process transistors used for realizing the gate driver becomes a topic to be discussed.